Background: Current treatment options for acute myeloid leukemia (AML) are diverse, including intensive chemotherapy (IC), low intensity therapy, best supportive care (BSC), and hospice care. Despite continued development of new therapies, recent data suggest that approximately 60% of older US patients remain untreated, but reasons for this are not well understood. By gathering insights from physicians, patients, and their family members, this study aims to better understand the factors that influence treatment decisions for adults with AML. Methods: Physicians in the US (n=4), UK (n=3) and Canada (n=3), and 15 US AML patient-family member dyads took part in one-on-one, 60-minute semi-structured interviews. Each participant rated a series of factors on a scale from 0 (not at all important) to 3 (very important) to determine their importance in treatment decision-making. Among the 15 adults with AML (>65 years, not taking IC) interviewed thus far, 13 had not received any treatment. Additional interviews are scheduled in the UK and Canada with patients having varied treatment experiences (data will be available for presentation). Results: To date, findings highlight the key role perceptions of side effects and patient health play in treatment decision making. A fear of treatment side effects was the primary reason patients (n=9/13) opted not to receive treatment. For the 2/15 study patients who had received treatment, side effects were considered the worst part of their treatment experience. Physicians also stated patients on BSC would be more willing to take low intensity treatments if risks (e.g., side effects) were minimized. Patients (n=11/15), their family members (n=11/15), and physicians (n=10/10) agreed that patients’ health (including age and comorbidities) influenced if treatment was pursued. Additionally, US physicians suggested that some patients have little desire to pursue treatment, with patients’ perception of low intensity therapy having poor efficacy and proximity of care influencing their choice for BSC or hospice care. Further analysis will explore other factors influencing patients’ treatment decisions and differences among patients who receive treatment versus those who do not. Conclusions: The treatment decision-making process for older adults with AML is complex and multifactorial. Understanding factors that influence treatment decisions is important if drug developers and prescribers are to ensure the availability of therapies that better align with individual patients’ needs.